Cordless Power Tool - corder...

[TaDa]

I'm enjoying this thread more and more - although for people using it as a reference its a bit of a mess.

I now understand the the need for the different sorts of car batteries when used in expedition vehicles - some are for starting your car and, perhaps running the winch, some are for running your ancilliaries (this'll be the deep cycle ones!)

So I need to find myself a source of reasonably priced sealed LA deep-cycle 6V batteries - any suggestions?

 

[tcmtech]

UPS batteries. They are designed for short term high current loads followed by the possibility of having to wait for some time before being recharged.

Pick your shape and size and go from there.

 

[TaDa]

Yikes! They're pricier than the ni-cds I'll be replacing - still they'll be a lot less fiddle when I've sorted this all out.

I see a "bat-belt" with lead acid batteries powering the strimmer and hedge trimmer - this is all coming together

I just need a cheaper source of UPS batteries...

 

[4pyros]

Yikes! They're pricier than the ni-cds I'll be replacing - still they'll be a lot less fiddle when I've sorted this all out.

I see a "bat-belt" with lead acid batteries powering the strimmer and hedge trimmer - this is all coming together

I just need a cheaper source of UPS batteries...

Try looking for SLA batterys instead of UPS batterys.

 

[MrAl]

Hi,

I use SLA batteries for my cordless. Works great and has lots of reserve capacity with even a 8 AHr size and not too hard to carry. I also have a larger camera shoulder bag i can use to carry the battery and keep it connected, so using it remotely is a little easier that way.

I also have a large Jump Pack which is just a fancy 12v SLA too, and i've used that on occasion but it is bigger and heavier so harder to carry around even though it has a nice handle.

You can also make up your own little carry box to make it easier to carry.

Charging does take longer but if you dont have to use the drill all day it usually works out ok, or else have two batteries on hand.

 

[4pyros]

Thats a doozy of a diode - 50Amps

I made it out of smaller diodes I had laying around. I just put a bunch in parallel.
8 gage jumper cable seems way over kill and hard to work with when trying to hold a hand tool.

 

[TaDa]

The jumper cables are, I think, 12 gauge - they're quite thick but still quite flexible - I think they're ok - if they don't overheat but are too inflexible I can always turn them back into jumper cables and use thinner wire.

For now, I'll chance the lack of diode as I need to crack on with the woodwork and don't have any diodes to hand (!!)
(What no diodes? What sort of person is this? )

I'll be using the car battery too - but I'll keep an eye out for SLA batteries for the ultimate solution.

 

[4pyros]

but I'll keep an eye out for SLA batteries for the ultimate solution.

You could find some quick for use on kids Power Wheels toys. Most use 6 volt SLAs.
Thay are in Walmart and K Mart.

 

[TaDa]

I'm in the UK - ASDA and Tesco don't hold a candle to the shops you have access to - I saw a guy buy a gun at a Walmart once!
SLA batteries in Maplins (our equivalent to Radio Shack) start at around £15 and the ones you really want at around £25!
ebay are cheaper of course (even with postage) but you have to take a punt with an ebay seller :-(

Now, having been through all this pain I see I can buy 10 Li-ion 18650 3.7v batteries for around £19 - allegedly 4000mAh - and a separate charger for £20.
5 of them should easily drive my circular saw and another 5 could be charged at the same time
I suspect they could easily fit into the cavity left in the 15 sub-c battery pack - perhaps in an easily changeable way.

Decisions decisions!

 

[tcmtech]

Personally I would not be too worried about running off of a common car battery.

Even a smaller automotive starting battery will give you enough run time at peak power to burn your motor out long before the battery gets run down to far enough to do any damage.

Given a common 30 ah lawn and garden battery still has more than 16 times the energy of a single 12 volt 1800 mah nicad pack you would have to be doing some serious cordless tool work to use up the equivalent power of 16 battery packs in one single day.

If yo are running a single cordless tool that hard you should really be running corded AC powered unit at that point.

 

[MrAl]

Hi,

If i remember right the diode i used in mine was a 35 amp stud mount rectifier diode. That takes a lot of current to blow out. But i used it mainly to drop a little more voltage because the drill motor was rated for 9.6v and the battery was 12v, and i did not want to overpower the motor. I figured with a little line drop the voltage should be within an acceptable range that way. But yes the diode helps with reverse connection too, and the drill has a solid state speed regulator in it which would probably be damaged if the voltage was reversed. But i was mainly adding the diode for the extra little voltage drop.

To protect against reverse connection which is good in a motor with speed regulation, i color code the leads that connect to the battery. I paint one lead bright red with a spray can of paint. This helps identify the positive lead right away.
Another idea is to wire in a connector to the battery and use that instead of connecting individual leads to the battery. The connector would be polarized so it can not be plugged in backwards.
Still yet another idea is to install single wire connectors to the battery posts, making one a different size so the positive can not be plugged into the negative or vice versa.
Another way that also does not drop any voltage is to install a heavy current switch in line with the motor. When the drill is connected to the battery have the switch turned off. With an LED connected BEFORE the switch, the LED will light up if the polarity is correct which says that it is OK to turn the switch on for the drill motor itself. If the LED does not light then the polarity is wrong so it has to be reversed first. You could also use red and green LED's for this which would be nice i think. Red means reversed, Green means "OK to turn the drill on". This is the method used when there is heavy current involved and we dont want to loose a voltage drop somewhere like what happens when using a diode. Diodes can drop 1v or more under heavy current conditions and sometimes that's just too much.

 

[TaDa]

I had all the bits to do a pucker job - jump leads, anderson connectors, big battery and the connector from the old battery pack but I was in too much of a rush to do the proper job.

So instead I just used the jump leads to the bits of wire hanging off the batter pack. I very carefully duck taped them in place to stop them shorting and, when I finished, I realised I'd put the black jumper lead on the red lead - doh! So for my quick bit of work I had to remember to put them on the battery the 'wrong way'

The whole thing worked a treat - 3 5 foot cuts achieved!

Now I can do the proper job at my leisure....

...The joint will need to take the abuse of being attached to a cord(less)ed tool...

....is there a cheaper way to crimp and solder the anderson connector to the cable without the need to buy some hydraulic crimpers like this site suggests:

https://www.wheelchairdriver.com/crimp-solder.htm​

The crimpers cost around £45 which for the dozen or so connections I will make in total is a little expensive

 

[MrAl]

Hi,

What size wire are you using and what kind of connectors do you need to connect to them, have a pic?

 

[4pyros]

is there a cheaper way to crimp

You can try to dimpel them with a nail punch and hammer.

 

[TaDa]

What size wire are you using and what kind of connectors do you need to connect to them, have a pic?

The pictures in the link are pretty much right - even the wire.

You can try to dimpel them with a nail punch and hammer.

I think I might be underselling myself on the crimping tool.
When I first saw them I thought the measurements were wire diameter - but they're wire area.
So am I right in thinking that a pair of these would do most of the typical crimping around a car?

**broken link removed**​

The 4mm is 'square mm' - which is about 2.2mm diameter - which is roughly 'car' crimp connector size right?

 

[4pyros]

The pictures in the link are pretty much right - even the wire.



I think I might be underselling myself on the crimping tool.
When I first saw them I thought the measurements were wire diameter - but they're wire area.
So am I right in thinking that a pair of these would do most of the typical crimping around a car?

**broken link removed**​

The 4mm is 'square mm' - which is about 2.2mm diameter - which is roughly 'car' crimp connector size right?

No Hexagonal crimp's are only good for certain connectors.

 

[TaDa]

No Hexagonal crimp's are only good for certain connectors.

Oh, this is a whole new industrial level of electronics for me.

Can anyone recommend a reasonably priced crimping tool that will do the anderson connectors and yet remain useful to me for 'normal' car crimping duties?

(I'm hoping these things aren't like torque wrenches - but I fear the worst - no matter which ones you have you always need another one)

 

[4pyros]

(I'm hoping these things aren't like torque wrenches - but I fear the worst - no matter which ones you have you always need another one)

Sorry but its true, every different terminal will have its own crimper. Most of the differentness will be in how they crimp the insolation, witch the anderson connectors don't even do.

 

[tcmtech]

If it was me I would just use a rounded off punch or bolt to dent the connectors enough to get them to hold the wire and then just solder them the rest of the way.

If soldered right and taped or heat shrinked properly they shouldn't give you any problems.

There is no need to over complicate things. It's just a big connector and you're only carrying 30 - 40 amps for a few seconds at peak loads for gosh sakes.

 

[TaDa]

Thanks all for spotting the relative uselessness of those crimpers to me - that saved me buying a £40+ white elephant

So back to the punch and hammer then...sounds like a pub....hmm...